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1.
Adv Mater ; : e2404694, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38857532

RESUMEN

Due to the broadband response and low selectivity of external light, negative photoconductivity (NPC) effect holds great potential applications in photoelectric devices. Herein, different photoresponsive carbon nanodots (CDs) are prepared from diverse precursors and the broadband response from the NPC CDs are utilized to achieve the optoelectronic logic gates and optical imaging for the first time. In detail, the mcu-CDs which are prepared by the microwave-assisted polymerization of citric acid and urea possess the large specific surface area and abundant hydrophilic groups as sites for the adsorption of H2O molecules and thereby present a high conductivity in dark. Meanwhile, the low affinity of mcu-CDs to H2O molecules permits the light-induced desorption of H2O molecules by heat effect and thus endow the mcu-CDs with a low conductivity under illumination. The easy absorption and desorption of H2O molecules contribute to the extraordinary NPC of mcu-CDs. With the broadband NPC response in CDs, the optoelectronic logic gates and flexible optical imaging system are established, achieving the applications of "NOR" or "NAND" logic operations and high-quality optical images. These findings unveil the unique optoelectronic properties of CDs, and have the potential to advance the applications of CDs in optoelectronic devices.

2.
J Phys Chem Lett ; 12(16): 4079-4084, 2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33881881

RESUMEN

Herein, the negative photoconductivity (NPC) effect has been observed in nanodiamonds (NDs) for the first time, and with illumination under a 660 nm laser lamp, the conductivity of the NDs decreases significantly. The NPC effect has been attributed to the trapping of carriers by the absorbed water molecules on the ND surfaces. A humidity sensor has been constructed based on the NPC effect of the NDs, and the sensitivity of the sensor can reach 106%, which is the highest value ever reported for carbon-based humidity sensors.

3.
Chin Med J (Engl) ; 123(22): 3206-11, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21163116

RESUMEN

BACKGROUND: The prognosis is poor for patients with relapsed or refractory non-Hodgkin's lymphoma (NHL). The main reason for poor prognosis is multidrug resistance (MDR), for which the main phenotype is overexpression of P-glycoprotein (P-gp). This study explored the efficacy of ligustrazine as a salvage agent in patients with relapsed or refractory NHL, and the relationship to P-gp expression. METHODS: Sixty patients were randomized to a reversal agent group, receiving ligustrazine plus chemotherapy, and a control group, receiving chemotherapy alone. Flow cytometry was performed to evaluate P-gp expression. RESULTS: In the 56 patients we were able to evaluate, there was no statistically significant difference in progression-free survival (PFS) in the two groups (P = 0.0651), but the reversal agent group had a higher overall response rate (ORR) than did the control group (P = 0.048). Forty-one of 56 patients had P-gp(+) tumor cells. Among these patients, six of eighteen patients in the reversal agent group and in the control group had complete remission or complete remission/unconfirmed (CR+CRu) reflecting a significant advantage in the reversal agent group (P = 0.048). Patients with P-gp(+) tumor cells in the reversal agent group had a higher overall response rate (ORR) than did the control group (11/18 vs. 6/23, P = 0.024). Kaplan-Meier Survival curve and log-rank test demonstrated that patients with P-gp(+) tumor cells in the reversal agent group had longer progression-free survival than did the control group (P = 0.0464). A small number of patients who received ligustrazine had a decrease in blood pressure. CONCLUSION: Ligustrazine as a salvage agent in combination with chemotherapy can elevate response rate, prolong PFS with manageable toxicity, and correlate with P-gp expression in relapsed or refractory NHL.


Asunto(s)
Bloqueadores de los Canales de Calcio/uso terapéutico , Linfoma no Hodgkin/tratamiento farmacológico , Pirazinas/uso terapéutico , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Adulto , Anciano , Femenino , Humanos , Linfoma no Hodgkin/metabolismo , Linfoma no Hodgkin/mortalidad , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
4.
Zhonghua Zhong Liu Za Zhi ; 30(4): 317-9, 2008 Apr.
Artículo en Chino | MEDLINE | ID: mdl-18788642

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of a weekly schedule of low dose-intensity docetaxel monochemotherapy for patients with anthracycline-resistant metastatic breast cancer (MBC) in poor physical status. METHODS: Thirty MBC patients who were previously exposed to anthracycline treatment received docetaxel alone at a dose of 30 mg/m2 on D1, D8 and D15, repeated every 4 weeks for a maximum of 6 cycles. RESULTS: Of the 30 evaluable patients, 2 (6.7%) achieved a complete response, and 9 (30.0%) a partial response, with an overall objective response rate of 36.7% (95% CI: 20.5%-53.9%). The most common adverse event was hematologic toxicity. After an average follow-up of 15.0 months, the median time to progression (TTP) was 8. 5 months and the median overall survival (OS) had not reached yet at the end of follow-up. CONCLUSION: The weekly low dose-intensity docetaxel monochemotherapy is effective and well-tolerated in patients with anthracycline-resistant metastatic breast cancer in poor physical status.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/tratamiento farmacológico , Taxoides/uso terapéutico , Adulto , Anciano , Antraciclinas/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Carcinoma Lobular/tratamiento farmacológico , Carcinoma Lobular/patología , Docetaxel , Resistencia a Antineoplásicos , Femenino , Estudios de Seguimiento , Humanos , Leucopenia/inducido químicamente , Metástasis Linfática , Persona de Mediana Edad , Náusea/inducido químicamente , Metástasis de la Neoplasia , Estadificación de Neoplasias , Inducción de Remisión , Tasa de Supervivencia , Taxoides/administración & dosificación , Taxoides/efectos adversos
5.
Am J Clin Oncol ; 31(3): 259-63, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18525305

RESUMEN

OBJECTIVE: The aim of the study was to assess the toxicity and the clinical activity of biweekly oxaliplatin (OXA) in combination with continuous infusional 5-fluorouracil (5-FU) and leucovorin (LV) administered every 2 weeks (modified FOLFOX-4 regimen) in elderly patients with advanced gastric cancer (AGC). PATIENTS AND METHODS: A total of 44 previously untreated AGC patients aged 65 or older were treated with OXA 85 mg m-2 on day 1, LV 200 mg m-2 as a 2-hour infusion followed by a 22-hour infusion of 5-FU 1000 mg m using a multichannel programmable pump, repeated for 2 consecutive days every 2 weeks. RESULTS: All patients were assessable for toxicity and 40 patients for response. Median age was 69 years (65-83). The response rate according to Response Evaluation Criteria in Solid Tumors (RECIST) criteria was 52.5% (95% confidence interval: 44.6%-68.0%) with 3 complete responses, 18 partial responses, 11 stable diseases, and 8 progressions. Median time to progression was 6.5 months and median overall survival was 10.0 months. Toxicity was generally mild. Grade 3 hematologic toxicities of neutropenia, anemia, and thrombocytopenia were in 6.8%, 2.3%, and 4.5% of the patients, respectively. No grade 4 hematologic toxicities occurred. Grade 1 peripheral neuropathy was a common event (34.1%), whereas grade 3 peripheral neuropathy was recorded in only 1 (2.3%) patient. An acute hypersensitivity reaction was observed in 1 patient during administration. CONCLUSION: The modified FOLFOX-4 regimen is an active and well-tolerated chemotherapy for elderly patients aged > or =65 years with AGC. OXA may occasionally cause mild hypersensitivity.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Neoplasias Gástricas/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Esquema de Medicación , Hipersensibilidad a las Drogas/etiología , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Granisetrón/administración & dosificación , Enfermedades Hematológicas/inducido químicamente , Humanos , Infusiones Intravenosas , Leucovorina/administración & dosificación , Masculino , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Premedicación , Neoplasias Gástricas/mortalidad , Tasa de Supervivencia , Resultado del Tratamiento
6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 14(4): 763-7, 2006 Aug.
Artículo en Chino | MEDLINE | ID: mdl-16928317

RESUMEN

This study was aimed to investigate the relationship between endostatin and vascular cell adhesion molecule-1 (VCAM-1) expressions on bone marrow stromal cells (BMSC) in mice after bone marrow transplantation (BMT) and effect of ligustrazine on their expressions. The mice were randomly divided into 3 groups: normal group (without treatment), saline group (control of BMT) and ligustrazine group (BMT + ligustrazine). BMT mouse models were established. The normal group was not treated, the saline group was given normal saline (0.2 ml/mouse, twice a day) through gastric tube, while the ligustrazine group was given ligustrazine (0.2 ml/mouse, twice a day) also through gastric tube. On day 7, 14, 21 and 28 after BMT, mice were killed by euthanasia. The expression levels of endostatin and VCAM-1 in bone marrow stromal cells were detected by immunohistochemistry and RT-PCR analysis respectively. The results showed that the endostatin protein mainly expressed in nuclei of BMSCs, the VCAM-1 protein mainly expressed in plasma of BMSCs. On day 7, 14, 21 after BMT the expression levels of endostatin mRNA and protein in ligustrazine and saline groups were significantly lower than that in normal group (P < 0.01 or P < 0.05), while their expression levels in ligustrazine group were lower than that in saline group. On day 28 the expression levels in saline group returned to normal, while the expression levels in ligustrazine group not were normalized. On day 7, 14, 21 after BMT the expression levels of VCAM-1 mRNA and protein in ligustrazine and saline groups were significantly lower than that in normal group (P < 0.01 or P < 0.05), but their expression levels in ligustrazine group were significantly lighter than that in saline group (P < 0.01 or P < 0.05). On day 28 the VCAM-1 expression level in ligustrazine group returned to normal, while its expression level in saline group not were normalized. The difference between these two groups was significant (P < 0.01). Correlation analysis revealed that there was a negative correlation between endostatin and VCAM-1 expression in saline group, there was a positive correlation between endostatin and VCAM-1 expression in ligustrazine group. It is concluded that the endostatin can influence hematopoiesis in bone marrow by affecting VCAM-1 expression on BMSC and hindering connection between stromal cells and hematopoietic cells as well as extracellular stroma and hematopoietic cells, while ligustrazine can enhance the adhesion molecule expression on stromal cell surface of bone marrow in BMT-mice, accelerate the homing and proliferation of HSPC in bone marrow after BMT, meanwhile can promote the repair of bone marrow microenvironment, accelerate hematopoietic reconstitution of bone marrow after BMT through feedback regulation of endostatin expression of BMSC in BMT-mice.


Asunto(s)
Células de la Médula Ósea/metabolismo , Trasplante de Médula Ósea , Endostatinas/biosíntesis , Células del Estroma/metabolismo , Molécula 1 de Adhesión Celular Vascular/biosíntesis , Animales , Células de la Médula Ósea/citología , Endostatinas/genética , Femenino , Masculino , Ratones , Ratones Endogámicos BALB C , Pirazinas/farmacología , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Distribución Aleatoria , Molécula 1 de Adhesión Celular Vascular/genética
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